This is a 6-Month, double-blind, randomized, placebo-controlled, parallel- group, multicenter trial in patients with noninsulin-dependent diabetes mellitus. Following a 1-week screening period, patients will discontinue all current phrmacological treatment for diabetes and enter a 2-week diet therapy baseline study period, after which patients will be randomized in parallel-treatment arms to placebo or troglitazone, 100, 200, 400, or 600 mg.